


A Lesson with Slim

by SoloShikigami



Category: Undertale (Video Game)
Genre: Daddy Kink, First Time, M/M, Masturbation, Swapfell Papyrus - Freeform, Underswap Papyrus
Language: English
Status: Completed
Published: 2016-09-25
Updated: 2016-09-25
Packaged: 2018-08-17 07:33:31
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,846
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8135642
Author URL: https://archiveofourown.org/users/SoloShikigami/pseuds/SoloShikigami
Summary: Slim is feeling a little uncomfortable, but doesn’t know how to deal on his own… Good think Papa Papy is there to lend a hand.





	

**Author's Note:**

  * For [NearlyDeadZed](https://archiveofourown.org/gifts?recipient=NearlyDeadZed).



> Birthday gift for NearlyDeadZed!

            Papyrus watched the skeleton sitting on the other side of the couch carefully. It had been a few weeks since he seemed to drop in out of nowhere, looking fairly bruised and broken. Apparently, his Sans had become very violent and in a panic, he had somehow hopped dimensions as he teleported. It was a one in a million chance, and in Papyrus' eyes, it was a good thing.

            This other Papyrus, who they had dubbed Slim, was hysterical when he realized what he did. It had taken the two brothers some time to calm him down and convince him to stay in the house. Then there was an awkward few days when Slim tried to perform sexual acts for them in return for their care. Sans had been especially freaked out and embarrassed; not only was he not happy to have such a horrible-sounding double in some other dimension as Slim' Sans seemed to be, but also because while not stupid, his inexperience made him nervous.

            Papyrus wasn't particularly bothered by it, in fact, he wouldn't have minded but it was for all the wrong reasons. He didn't want a blowjob in exchange for simple hospitality.

            Slim didn't say much, he didn't really speak until he was certain he had permission. Papyrus started to wonder what was going through his head as he seemed to be agitated or worried about something.

            "So are you going to tell me why you look like you ate the Queen's pie or something?" Papyrus ventured with an amused tone.

            Slim's head snapped up as if realizing just then that he wasn't alone in the room.

            “What do you mean?” he asked.

            Papyrus chuckled. “You look like you’re guilty of something. Are you all right?”

            “Well,” Slim looked away, and then he sighed and looked at his lap. “No, of course I’m not all right. I’m stuck in another dimension and my Lord has no idea where I am. He must be worried sick.”

            “I’m sure we’ll find a way to get you back there,” Papyrus said. “But this has been on your mind since you got here, it looks like there’s something else bothering you.”

            Slim cowered back against the couch a little. “I’m, uh, horny,” he mumbled.

            Papyrus’ eyes widened a little at the more than honest admission. “Oh, well, you can always go into the bedroom, the bathroom, or I could go take a walk.”

            Slim blinked at him. “What do you mean? I can’t do anything without M’lord here to, you know…”

            “What? Does he keep you from masturbating as well? That’s quite cruel.”

            “What’s masturbating?”

            Now it was Papyrus’ turn to blink at Slim. “You’ve never touched yourself?”

            “Well, no, why would I?”

            “You’ve never touched your own cock?”

            “No.”

            “Your pussy?”

            “No.”

            “Any part of your body to give yourself sexual pleasure?”

            “Why? I thought you were supposed to have sex with other people.”

            Papyrus scratched the back of his skull. “Oh boy. Nah, man, this is something you can do yourself to get off.”

            “Oh.”

            Awkward silence filled the room. Papyrus was desperately trying to think of a way to make it better, but to his surprise, Slim spoke first.

            “Could you teach me?” he asked quietly.

            “Are you sure? I mean, you’re not going to get in trouble because someone else was with you and stuff?”

            A devious sort of smile slowly spread across his face. “What M’lord doesn’t know won’t hurt me.”

            Papyrus smirked at him. “I like the way you think. Come on, I’m sure Sans won’t be home for a while, but just in case, I don’t think I’d want him to walk in on something he wasn’t ready to handle.”

            Papyrus stood up and Slim eagerly followed, moving close to Papyrus before he started towards the stairs. Papyrus tilted his head, looking at Slim for a moment before reaching up to caress the top of his head.

            “Daddy’s going to take good care of you,” he murmured.

            “Should I call you that?” Slim asked almost eagerly.

            Again, Papyrus took a moment to consider. “That sounds nice. Come along.”

            Slim reached down and took Papyrus’ hand as he turned and lead him upstairs. They went inside his room and he shut and locked the door.

            “Uhm, Daddy? Can I ask for something?” Slim asked.

            “Sure, what is it?” Papyrus answered.

            “C-can I have a kiss before we start?”

            Papyrus smiled. Slim looked absolutely adorable; his feet were turned in slightly, his fingers fidgeted against one another, and he was looking down at the ground, very much looking like a child asking for a treat.

            “I don’t see why not,” Papyrus said, moving close and tilting Slim’s head up by his chin with a crooked finger.

            Slim let out a happy noise as their mouths met. Papyrus slid his tongue across the other’s teeth, Slim instantly opened his mouth and he groaned as his talented tongue wound and pressed against his.

            “Mmm, you’re very good at that,” Papyrus said, thumb running across Slim’s chin.

            “Thank you, Daddy,” he murmured.

            “Good boy. Now, take off your clothes.”

            Papyrus moved to his bed and dropped down on it, his legs hanging off the edge and leaning back on his elbows. He watched as Slim slowly undressed himself; there were no flourishes or attempts to make it into a striptease, it was just Slim slowly sliding his tight pants down his slender legs, shrugging off his jacket, then pulling the white, ribbed tank top over his head. He fingered the red collar with golden spikes for a moment, almost as if considering taking it off, even though he couldn’t even if he wanted to.

            “You’re such a good boy,” Papyrus praised, hoping to keep Slim’s mind on the matter at hand. “Come and sit by Daddy.”

            Slim nodded. Papyrus sat up and spread his legs, and when Slim was close enough he helped to guide him to sit between his knees and to lay back onto him. Papyrus pressed a kiss to the side of his skull.

            “Good, very good, Daddy is pleased,” Papyrus murmured. “Now, when you do this, try to relax. Close your eyes if you need to.”

            Slim nodded, his eyes sliding shut. Papyrus smiled at the complete trust Slim had in him and he reached down for his hands.

            “Okay, now you let your hands explore your body. Since you’ve been touched before, you have a pretty good idea on what spots turn you on. Where does Sans touch you that feels good?”

            Slim shook a little at the mention of his lover’s name. “Uh, my ribs, I think, especially the ones at the bottom.”

            “Yeah? I’m a little sensitive there myself,” Papyrus murmured, and he guided Slim’s hands to the area.

            Slim followed, but he also picked up on what he was supposed to do and trailed his fingertips lightly across his bones.

            “Mmm, that feels nice,” Slim said.

            “Good, good,” Papyrus nuzzled the side of his face. “How about your spine? Is that sensitive?”

            “Maybe? I’m not sure, actually,” Slim said.

            “Go on and find out.”

            Slim’s slightly shaking fingers moved down from his ribs and brushed down his spine. He sighed, moving up and down lightly.

            “Oh, damn, that does feel good,” Slim arched into his own touch a little.

            “Excellent, you’re doing so well,” Papyrus said.

            Slim took a few minutes to explore his own spine; he fingered at some of the discs between the vertebrae, touched softly, then scrapped his fingers, finding what kind of touch sent shivers across the rest of his bones.

            Papyrus watched intently. It was oddly intimate, seeing someone exploring their body like this. Slim’s face was quite intriguing as it went from neutral to curious to excited. His breathy sighs made Papyrus smile.

            “You’re such a good boy,” he murmured, reaching up to stroke Slim’s skull with one hand as his other went to cover Slim’s hand again to guide it. “Now, concentrate on forming whatever you feel like playing with today.”

            Slim nodded, and Papyrus figured it was because of having to form genitalia on command for who knows how long, because the instruction was barely out of his mouth when orange light filled the room as Slim’s cock came into existence.

            “Wow, I’m impressed,” Papyrus said. “Now, the same principle applies; just touch it how you like, or how you would want it to be touched.”

            He could feel Slim’s hand shaking as he slowly moved down to take the orange rod into his hand. His thumb brushed across the head and he groaned, his hips bucking up a little. Papyrus motioned his hand down a little, and Slim caught on quick and he started to stroke it slowly.

            “Oh, stars, oh stars,” Slim moaned, dropping his head back against Papyrus’ shoulder.

            “Good boy, such a good boy,” Papyrus said.

            Slim started to move his hand faster, his breath quickened, and he felt a pressure beginning to curl in his soul.

            “Daddy,” Slim moaned. “I feel strange.”

            Slim’s hand began to falter, so Papyrus wrapped his hand around his again and helped him go back to a slow pace.

            “It’s ok,” Papyrus whispered, pressing a kiss to the side of Slim’s skull. “Sometimes it feels strange, just relax and know it’s all right. This is going to feel so good.”

            “A-all right,” Slim stammered.

            “Trust me.”

            Papyrus continued to guide him, and he could tell he was getting closer to his peak as his breathing became erratic and his bones grew warmer.

            “Daddy,” Slim whined. “Please, Daddy, I can’t anymore.”

            It occurred to Papyrus suddenly that Slim probably always has to ask permission to do everything, which included his release.

            He figured they could work on that later. But for now…

            “Such a good boy,” Papyrus purred. “Cum for me, sweet boy.”

            He could feel Slim gripping himself tighter just before his back arched as he came; papyrus quickly wrapped an arm around him to keep him steady as pale orange cum covered both of their hands and dripped onto the floor. Slim moaned as his body relaxed, dropping back into Papyrus’ lap, panting.

            “So good,” Papyrus said with a small chuckle, pumping Slim’s cock a few more times, milking the rest of his seed.

            Slim could only whimper at the final strokes before his body shuddered with the final wave of pleasure that washed over him.

            “Th-thank you, Daddy,” Slim murmured, looking up at Papyrus.

            “You’re quite welcome,” Papyrus smiled and leaned down to kiss him gently. “We’ll do this again when you’re feeling pent up, and soon you’ll be able to do it whenever you need to.”

            Slim seemed to pout a little. “It was nice, but it doesn’t feel as good as being with someone else.”

            “Mm, that is true,” papyrus said, stroking the side of his face. “This is more for a desperate times calling for desperate measure situation. In the meantime, you have me, all right?”

            Slim nodded. “All right, thank you.”

            Papyrus smiled and kissed him again. “Anytime, my sweet Slim.”

 


End file.
